The formula for the

area of a triangle is A is equal to 1/2 b times

h, where A is equal to area, b is equal to

length of the base, and h is equal to the

length of the height. So area is equal to

1/2 times the length of the base times the

length of the height. Solve this formula

for the height. So just to visualize

this a little bit, let me draw a triangle here. Let me draw a triangle just

so we know what b and h are. b would be the

length of the base. So this distance

right over here is b. And then this distance

right here is our height. That is the height

of the triangle– let me do that at a lower

case h because that’s how we wrote it in the formula. Now, they want us to solve

this formula for the height. So the formula is area is

equal to 1/2 base times height. And we want to solve for h. We essentially want

to isolate the h on one side of the equation. It’s already on the

right-hand side. So let’s get rid of everything

else on the right-hand side. So we can do it– well, I’ll

do it one step at a time. We could kind of skip

steps if we wanted to. But let’s see if we can

get rid of this 1/2. So the best way to get

rid of a 1/2 that’s being multiplied by

h is if we multiply both sides of the equation

by its reciprocal. If we multiply both sides of

the equation by 2/1 or by 2. So let’s do that. So let’s multiply–

remember anything you do to one side

of the equation, you also have to do to the

other side of the equation. Now, what did this do? Well, the whole point

behind multiplying by 2 is 2 times 1/2 is 1. So on the right-hand

side of the equation, we’re just going to have a bh. And on the left-hand side of

the equation, we have a 2A. And we’re almost there, we

have a b multiplying by an h. If we want to just

isolate the h, we could divide both sides

of this equation by b. We’re just dividing both sides. You can almost view b as

the coefficient on the h. We’re just dividing

both sides by b. And then what do we get? Well, the right-hand

side, the b’s cancel out. On the left-hand side, we’re

just left with 2A over b. So we get h– and I’m just

swapping the sides here. h is equal to 2A over b. And we’re done. We have solved this

formula for the height. And I guess this

could be useful. If someone just gave

you a bunch of areas and a bunch of base

lengths, and they said keep giving me the

height for those values, or for those triangles.

Thank you so much, I had no clue how to do this in class but now I do!

thanks

I love you

I got h = A/(1/2)*b

Needed a refresher. Thanks!

bh

i swear, with out kahn academy i would be failing algebra

You are the best teacher I have ever seen

why do we even learn this lol thnx tho

Holy biebs!!!! thankssssssss!!!!!!!!!!

another great video khan academy!!! ^ U ^

Thankz so much sir 😍

Interesting

Thank you so much

Life saver

so, Basically we isolates whatever we want to figure out

Ima fail my quiz

With khan academy im failingmath 🙂 XD

Oh my goodness, I did a test on this subject and completely failed! Watching this video makes me realize I was doing it all wrong! It now makes since, thank you very much for this video!

Better teacher than my real one